panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144 Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *382480 49611 0 0x2 0 0 syz-executor.0 db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827849f7) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280174e,ffffffff827ac70f,90,ffffffff8275b2f8) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:709 uvm_pagealloc(fffffd8077b0e6f8,1e85c000,0,3) at uvm_pagealloc+0x1ec sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8077b0e6c8,7a1720fd4000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1209 pmap_enter(fffffd8077b0e6c8,7a1720fd4000,68528000,3,20) at pmap_enter+0x29d sys/arch/amd64/amd64/pmap.c:2716 uvm_fault_upper_lookup(ffff800027f9a760,ffff800027f9a798,ffff800027f9a660,ffff800027f9a6e0) at uvm_fault_upper_lookup+0x2a1 sys/uvm/uvm_fault.c:895 uvm_fault(fffffd807e5a4740,7a1720fd5000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800027f9a8e0,7a1720fd57c0) at upageflttrap+0x80 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800027f9a8e0) at usertrap+0x20d sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a1720fd5840, count: 3 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144 ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827849f7) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280174e,ffffffff827ac70f,90,ffffffff8275b2f8) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:709 uvm_pagealloc(fffffd8077b0e6f8,1e85c000,0,3) at uvm_pagealloc+0x1ec sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8077b0e6c8,7a1720fd4000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1209 pmap_enter(fffffd8077b0e6c8,7a1720fd4000,68528000,3,20) at pmap_enter+0x29d sys/arch/amd64/amd64/pmap.c:2716 uvm_fault_upper_lookup(ffff800027f9a760,ffff800027f9a798,ffff800027f9a660,ffff800027f9a6e0) at uvm_fault_upper_lookup+0x2a1 sys/uvm/uvm_fault.c:895 uvm_fault(fffffd807e5a4740,7a1720fd5000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800027f9a8e0,7a1720fd57c0) at upageflttrap+0x80 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800027f9a8e0) at usertrap+0x20d sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a1720fd5840, count: -12 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800027f9a270 rbx 0 rdx 0 rcx 0 rax 0xffff8000216d6808 r8 0x101010101010101 r9 0x8080808080808080 r10 0x914fccf0aebcf047 r11 0x74200c03c9ede2bb r12 0 r13 0x1e85c000 r14 0 r15 0x1 rip 0xffffffff81b6dfdc db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff800027f9a260 ss 0 db_enter+0x1c: addq $0x8,%rsp ddb> show proc PROC (syz-executor.0) tid=382480 pid=49611 tcnt=1 stat=onproc flags process=2 proc=0 runpri=17, usrpri=83, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff8000216f6010,0xffff8000216e8000 process=0xffff8000ffff73c0 user=0xffff800027f95000, vmspace=0xfffffd807e5a4740 estcpu=33, cpticks=2, pctcpu=0.0, user=0, sys=2, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 37441 79788 21768 0 3 0x80 nanoslp syz-executor.3 37441 276181 21768 0 3 0x4000080 netcon syz-executor.3 37441 141402 21768 0 3 0x4000080 fsleep syz-executor.3 42085 61157 21657 0 3 0x82 nanoslp syz-executor.5 *49611 382480 21657 0 7 0x2 syz-executor.0 73593 68883 21657 0 3 0x82 nanoslp syz-executor.7 58026 510095 21657 0 3 0x82 nanoslp syz-executor.4 21768 135250 21657 0 3 0x82 nanoslp syz-executor.3 3543 436411 21657 0 3 0x2 biowait syz-executor.6 42438 24064 1 0 3 0x80 fsleep syz-executor.7 42438 419483 1 0 3 0x4000080 netio syz-executor.7 49557 357967 21657 0 3 0x82 nanoslp syz-executor.1 21565 121269 21657 0 3 0x82 nanoslp syz-executor.2 52592 335219 0 0 3 0x14200 bored sosplice 21657 91636 61438 0 3 0x2000082 thrsleep syz-fuzzer 21657 99015 61438 0 3 0x6000082 thrsleep syz-fuzzer 21657 162747 61438 0 3 0x6000082 thrsleep syz-fuzzer 21657 162292 61438 0 3 0x6000082 wait syz-fuzzer 21657 359923 61438 0 3 0x6000082 wait syz-fuzzer 21657 285298 61438 0 3 0x6000082 wait syz-fuzzer 21657 34806 61438 0 3 0x6000082 wait syz-fuzzer 21657 252735 61438 0 3 0x6000082 wait syz-fuzzer 21657 26842 61438 0 3 0x6000082 kqread syz-fuzzer 21657 150134 61438 0 3 0x6000082 thrsleep syz-fuzzer 21657 379643 61438 0 3 0x6000082 thrsleep syz-fuzzer 21657 443770 61438 0 3 0x6000082 wait syz-fuzzer 21657 403168 61438 0 3 0x6000082 wait syz-fuzzer 21657 89902 61438 0 3 0x6000082 wait syz-fuzzer 61438 254423 81671 0 3 0x10008a sigsusp ksh 81671 440682 88085 0 3 0x9a kqread sshd 20726 120825 1 0 3 0x100083 ttyopn getty 88085 388759 1 0 3 0x88 kqread sshd 62225 371689 68714 73 3 0x1100090 kqread syslogd 68714 148551 1 0 3 0x100082 netio syslogd 10644 64624 1 0 3 0x100080 kqread resolvd 2170 480301 46258 77 3 0x100092 kqread dhcpleased 57853 98631 46258 77 3 0x100092 kqread dhcpleased 46258 123629 1 0 3 0x80 kqread dhcpleased 77533 29695 0 0 3 0x14200 bored smr 85544 9590 0 0 2 0x14200 zerothread 17592 223129 0 0 3 0x14200 aiodoned aiodoned 1056 272904 0 0 3 0x14200 syncer update 59740 232437 0 0 3 0x14200 cleaner cleaner 52969 265304 0 0 3 0x14200 reaper reaper 73312 152994 0 0 3 0x14200 pgdaemon pagedaemon 17033 164453 0 0 3 0x14200 bored viomb 10267 429363 0 0 3 0x40014200 acpi0 acpi0 60399 324631 0 0 3 0x14200 bored softnet3 56765 268235 0 0 3 0x14200 bored softnet2 45896 506232 0 0 3 0x14200 bored softnet1 37405 424482 0 0 3 0x14200 bored softnet0 4864 415467 0 0 3 0x14200 bored systqmp 25700 279584 0 0 3 0x14200 bored systq 27170 433714 0 0 3 0x40014200 tmoslp softclock 82333 393773 0 0 3 0x40014200 idle0 1 381006 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10208 6436K 7938K 78643K 71165 0 pcb 13 18K 24K 78643K 13374 0 rtable 246 15K 15K 78643K 1638 0 pf 34 9K 10K 78643K 374 0 ifaddr 45 13K 14K 78643K 276 0 ifgroup 59 2K 2K 78643K 611 0 sysctl 4 1K 1K 78643K 6 0 counters 30 17K 17K 78643K 179 0 ioctlops 0 0K 2K 78643K 1647 0 iov 0 0K 28K 78643K 1655 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1621 101K 101K 78643K 15769 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 13K 78643K 443 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 3393 0 dirhash 12 2K 2K 78643K 60 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 12 41K 69K 78643K 17135 0 sigio 0 0K 0K 78643K 475 0 proc 58 59K 75K 78643K 1837 0 subproc 117 7K 11K 78643K 530 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 897 0 in_multi 99 7K 7K 78643K 445 0 ether_multi 1 0K 0K 78643K 12 0 mrt 1 0K 0K 78643K 7 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 223 996K 996K 78643K 223 0 exec 0 0K 1K 78643K 2280 0 pfkey data 0 0K 0K 78643K 3 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 8 62K 64K 78643K 10 0 UVM amap 476 448K 463K 78643K 158458 0 UVM aobj 131 4K 4K 78643K 134 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 386 0 NDP 13 0K 1K 78643K 226 0 temp 78 5916K 6116K 78643K 134039 0 kqueue 12 18K 28K 78643K 997 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 713 0 710 8 5 3 3 0 8 2 rtentry 112 406 0 293 4 0 4 4 0 8 0 unpcb 144 10800 0 10785 124 120 4 11 0 8 3 syncache 312 302 0 302 30 29 1 1 0 8 1 tcpqe 32 627 0 627 25 24 1 1 0 8 1 tcpcb 808 5095 0 5070 132 123 9 18 0 8 6 arp 88 68 0 50 1 0 1 1 0 8 0 ipq 40 13 0 13 7 7 0 1 0 8 0 ipqe 40 39 0 39 7 7 0 1 0 8 0 inpcb 336 23005 0 22977 233 224 9 23 0 8 6 ip6q 72 2 0 2 1 1 0 1 0 8 0 ip6af 40 3 0 3 1 1 0 1 0 8 0 nd6 104 111 0 84 1 0 1 1 0 8 0 pkpcb 40 198 0 198 7 6 1 1 0 8 1 kcovpl 48 35 0 26 1 0 1 1 0 8 0 ppxss 1160 43 0 43 12 12 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1567 0 1092 34 4 30 31 0 8 0 art_table 32 1568 0 1092 4 0 4 4 0 8 0 art_node 16 391 0 288 1 0 1 1 0 8 0 sysvmsgpl 40 19 0 8 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 3388 0 3378 1 0 1 1 0 8 0 shmpl 112 131 0 3 4 0 4 4 0 8 0 dirhash 1024 49 0 32 3 0 3 3 0 8 0 dino2pl 256 23857 0 22332 96 0 96 96 0 8 0 ffsino 240 23857 0 22332 91 0 91 91 0 8 0 nchpl 144 47215 0 46720 63 42 21 63 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 159007 0 159006 14 13 1 3 0 8 0 vcpupl 2048 78 0 2 10 0 10 10 0 8 0 vmpool 664 131 0 55 7 0 7 7 0 8 0 kstatmem 264 324 0 298 2 0 2 2 0 8 0 scxspl 216 142116 0 142115 49 47 2 8 1 8 1 plimitpl 152 1299 0 1283 1 0 1 1 0 8 0 sigapl 424 17398 0 17353 8 2 6 8 0 8 0 futexpl 64 181004 0 181002 1 0 1 1 0 8 0 knotepl 120 148198 0 148118 37 34 3 11 0 8 0 kqueuepl 184 2769 0 2761 41 40 1 4 0 8 0 pipepl 288 3474 0 3445 91 88 3 9 0 8 0 fdescpl 432 17359 0 17336 4 0 4 4 0 8 0 filepl 120 115657 0 115404 190 176 14 22 0 8 6 lockfpl 104 6844 0 6842 14 13 1 2 0 8 0 lockfspl 48 2746 0 2744 1 0 1 1 0 8 0 sessionpl 144 47 0 30 1 0 1 1 0 8 0 pgrppl 48 356 0 339 1 0 1 1 0 8 0 ucredpl 104 13075 0 13060 1 0 1 1 0 8 0 zombiepl 144 17358 0 17353 3 2 1 1 0 8 0 processpl 1008 17398 0 17353 10 3 7 9 0 8 0 procpl 680 42895 0 42834 24 17 7 9 0 8 0 sosppl 168 172 0 167 21 20 1 1 0 8 0 sockpl 456 34900 0 34854 642 628 14 45 0 8 7 mcl64k 65536 615 0 615 26 25 1 1 0 8 1 mcl16k 16384 281 0 281 31 30 1 1 0 8 1 mcl12k 12288 539 0 539 24 23 1 1 0 8 1 mcl9k 9216 346 0 346 36 35 1 1 0 8 1 mcl8k 8192 987 0 987 24 23 1 1 0 8 1 mcl4k 4096 2305 0 2305 13 12 1 1 0 8 1 mcl2k2 2112 121 0 121 35 34 1 1 0 8 1 mcl2k 2048 101291 0 101218 86 73 13 32 0 8 0 mtagpl 96 9954 0 8779 54 11 43 43 0 8 0 mbufpl 256 365648 0 363555 639 472 167 171 0 8 1 bufpl 288 34997 0 28600 458 0 458 458 0 8 0 anonpl 24 1518144 0 1504276 197 96 101 118 0 188 0 amapchunkpl 152 500996 0 500219 89 50 39 49 0 158 1 amappl16 200 26109 0 25590 97 68 29 41 0 8 1 amappl15 192 9 0 8 1 0 1 1 0 8 0 amappl14 184 225 0 213 2 1 1 2 0 8 0 amappl13 176 14 0 14 1 1 0 1 0 8 0 amappl12 168 18350 0 18324 2 0 2 2 0 8 0 amappl11 160 55 0 44 1 0 1 1 0 8 0 amappl10 152 67 0 57 2 1 1 1 0 8 0 amappl9 144 260 0 258 1 0 1 1 0 8 0 amappl8 136 802 0 679 5 0 5 5 0 8 0 amappl7 128 258 0 234 2 0 2 2 0 8 0 amappl6 120 715 0 702 1 0 1 1 0 8 0 amappl5 112 423 0 415 1 0 1 1 0 8 0 amappl4 104 695 0 669 2 1 1 2 0 8 0 amappl3 96 98987 0 98912 4 1 3 4 0 8 0 amappl2 88 18471 0 18400 3 0 3 3 0 8 0 amappl1 80 71576 0 71073 22 10 12 22 0 8 0 amappl 88 157293 0 157064 7 0 7 7 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 133 0 3 3 0 3 3 0 8 0 uaddrrnd 24 17490 0 17391 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 17490 0 17391 1 0 1 1 0 8 0 vmmpekpl 168 114486 0 114403 5 1 4 4 0 8 0 vmmpepl 168 1001471 0 999221 358 227 131 132 0 357 8 vmsppl 368 17489 0 17391 10 0 10 10 0 8 0 rwobjpl 24 227190 0 219521 50 2 48 48 0 8 0 pdppl 4096 34986 0 34858 741 600 141 142 0 8 13 pvpl 32 4369573 0 4350543 517 340 177 333 0 265 1 pmappl 216 17489 0 17391 6 0 6 6 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 2790 0 1735 31 0 31 31 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827849f7) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280174e,ffffffff827ac70f,90,ffffffff8275b2f8) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:709 uvm_pagealloc(fffffd8077b0e6f8,1e85c000,0,3) at uvm_pagealloc+0x1ec sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8077b0e6c8,7a1720fd4000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1209 pmap_enter(fffffd8077b0e6c8,7a1720fd4000,68528000,3,20) at pmap_enter+0x29d sys/arch/amd64/amd64/pmap.c:2716 uvm_fault_upper_lookup(ffff800027f9a760,ffff800027f9a798,ffff800027f9a660,ffff800027f9a6e0) at uvm_fault_upper_lookup+0x2a1 sys/uvm/uvm_fault.c:895 uvm_fault(fffffd807e5a4740,7a1720fd5000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800027f9a8e0,7a1720fd57c0) at upageflttrap+0x80 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800027f9a8e0) at usertrap+0x20d sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a1720fd5840, count: -12 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827849f7) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280174e,ffffffff827ac70f,90,ffffffff8275b2f8) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd80068c2980,fffffd8077b0e6f8,1e85c000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:709 uvm_pagealloc(fffffd8077b0e6f8,1e85c000,0,3) at uvm_pagealloc+0x1ec sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8077b0e6c8,7a1720fd4000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1209 pmap_enter(fffffd8077b0e6c8,7a1720fd4000,68528000,3,20) at pmap_enter+0x29d sys/arch/amd64/amd64/pmap.c:2716 uvm_fault_upper_lookup(ffff800027f9a760,ffff800027f9a798,ffff800027f9a660,ffff800027f9a6e0) at uvm_fault_upper_lookup+0x2a1 sys/uvm/uvm_fault.c:895 uvm_fault(fffffd807e5a4740,7a1720fd5000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800027f9a8e0,7a1720fd57c0) at upageflttrap+0x80 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800027f9a8e0) at usertrap+0x20d sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a1720fd5840, count: -12